Automatic trunk signaling system.



F. R. MJBERTY.

AUTOMATIC TRUNK SIGNALING SYSTEM.

APPLICATION FILED SEPT. 19', 1910.

Patented Nov. 17, I914.

4 sums-$112121 1.

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-3 ran/r RM Berfy. W by W F. R. MOBERTY.

AUTOMATIC TRUNK SIGNALING SYSTEM.

APPLICATION FILED SEPT. 19, 1910.

4 SHBETS SHEET 2.

NQQ u @2 Patented Nov. 17, 1914 //7ve/7f0r: Frank RM Ber/y. by

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NT: \3 58 w P. R. MGBERTY. AUTOMATIC TRUNK SIGNALING SYSTEM.

APPL'\GATION FILED SEPT. 19,1910.

4 W H r mm, W e Wm F w a m% Mm R 64. e m mg =2 3% :2 3w :fi h M H U r P t m W M L W 11 5 M 7 5 Q 1 e7 A .m h 1 i UNITED STATES PATENT OFFI )E.

FRANK B. MCBERTY, OF NEW ROCHELLE, NEW YORK, ASSIGNOR TO WESTERN ELEC- TRIC COMPANY, OF NEW YORK, N. Y., A CORPORATION OF ILLINOIS.

AUTOMATIC TRUNK SIGNALING SYSTIEIM.

Specification of Letters Patent.

Patented Nov. 17, 1914.

Application filed September 19, 1910. Serial No. 582,677.

To a7l whom it may concern Be it known that I, FRANK R. Mclinury, citizen of the United States, residing at New Rochelle, in the county of \Vestchestcr and State of New York, have invented a certain new and useful Improvement in Automatic Trunk Signaling Systems. of which the following is a full, clear, concise, and exact description.

My invention relates to telephone ex change systems of that class wherein lines from a semi-mechanical exchange, or from a subscribcrs automatic station, terminate in a manual exchange, and has for its object to provide means whereby the manual operator may automatically be informed of the designation of the line with which connection is desired.

In the specific form of my invention shown herein the object thereof is to provide a number indicator for the manual exchange and means for automaticall connecting the same to any line over whicli a call is transmitted from an automatic exchange, such indicator being adapted to display the number of the line wanted in response to the send ing or calling apparatus which in the automatic exchange determines the operation of the selecting mechanism.

In the operation of the system in which there is employed appropriate automatic calling apparatus, when the operator at the automatic station or at the semi-mo hauical exchange calls a line. she operates appropriate calling apparatus which i adapted to select the number of the called siiliscrilicus line. In case the line thus selected tenni nates in an automatic exchange the appara-- tus at that exchange will be operated auto matically to select a line corresponding to the number set ,up on the apparatus at the call ng end of toe line. In case, howerer, such a line terminates in an exchange of the manual type it is necessary or desirable to provide at that cxrr-hange some means governed by the conditions which select the line through the automatic exchange. which will operate to designate upon suitable indicating apparatus the number of the called line. As one means of accomplishing this signah ing I provide at the manual exchange a series of successively operated devices which are associated with the cord circuits at such exchan e in such a manner that when the line so eating apparatus at the semi-me chanical exchange or the subscribers automatic station has been operated, said devices will operate in regular sequence to complete the circuits necessary for displaying the signal designation of the line desired. More specifically the means for thus signaling the operator at the manual exchange embraces a plurality of successively operated registers each adapted to be moved through a definite distance to set up for display upon suitable indicators one digit. of the called number, the extent of movement of each of said registers being controlled by the calling apparatus. A line relay associated with each of said lines at the manual exchange is energized by the closing of the talking circuit andthereby causes the operation of sequence switches and an automatic trunk line finder, the operation oi which and the sequence switches establishes a circuit operatively connecting the fi st of said registers with the calling oi sending apparatus. At the completion of the operation of each of said registers, except the last, there is completed a circuit for the operation of the succeeding one thereof, and the operation of each determines the display oi a s gnal indiating one digit of the called number. i

One feature of mv invention involves means whereby a single ind cating apparatus may be successively utilized to care tor all of the calls coming over a pluralitv of lines term nating in one operators switchboard position.

Another feature of my intention pro des means whereby when a particular cord has been selected for recei ing a call and connected with the ind cating apparatus the re-- maining cords in the same onerators position will be prevented from becoming asso oiated with the numerical indicating appa ratus.

My in ention also includes means associated with the signaling system whereby u hen a cord has been seized and pre ared to receive the call a lamp will be lighted to designate to the operator which cord is in use.

My invention also in olves as one of its features a means whereby when the call for one line has been com leted and the talking circuit therefor set up by the o e a to" at the manual exchange the nume ical ind cat ng apparatus will he released f om connection with theparticular cord and rendered free to receive a call over any one of the remainin lines.

n the drawings in which the system is for convenience'illustrated in connection with a semi-mechanical exchange-Fi-gure 1 is a diagram illustrating so much as is necessary for an understanding of my invention of the sendin or controlling apparatus and circuits t erefor, at the originating exchange. Figs. 2, 3 and 4 when taken together form a diagram of the circuits and apparatus of the signaling means at the incoming exchange and show one form of my invention.

Like reference numerals designate like parts throughout th drawings.

In order to better understand the operation of the system brief reference will first be made to the various apparatus as used in connection therewith.

Referring first to the sending or controlling apparatus, the same. comprises generally a set of counting relays and a series of controlling switches or keys, together with a stepping relay for operating the counting relays in succession to close contacts in circuit with the switches or keys, and a cut-off relay adapted when the circuit is closed simultaneously by one of the counting relays and the particular key depressed to open a controlling circuit and thereby control apparatus in said circuit at the distant end thereof. As shown there are two series of counting relays, one series comprising relays l to 8, inclusive, which are adapted respectively to close contacts 61 to 68 in circuit with keys 51 to 58 and thecutoif relay Q3. The other series of counting relays 11 to 18, inclusive, is operated in alternate succession with said relays 1 to 8 to close circuits therefor. These two series of relays may be extended to include 7 any desired number. The stepping relay 24 is arranged to be energized and deiinergized intermittently during the movement of the registers of the numerical indicating apparatus, as will hereinafter be explained. Upon its first energization it closes contact 25 which completes a circuit from a battery 26 through contact 34, auxiliary counting relay 11 and back contact 28 of counting relay 1, thereby energizing relav 11 which closes a locking circuit for itself by way of its contact 29 and also closes contact 30. When the stepping relay is then dccnergized its armature falls back closing con-' tact 31, thereby completing a circuit for counting relay 1 from battery 26 through contact 32, winding of relay 1, back contact 33 of the second auxiliary relay 12, contact 30 of the first auxiliary relay 11 to ground and back to battery. Relay 1 is thereupon ejlergized and it like relay 11 closes a locking circuit for itself by way of contact 51 and the same time prepares through the. contact 28 a circuit for the next counting relay of the other series. As before stated, however, contact 61 is also in clr'cuit with the cut-off relay 23 and the first of a series of controlling switches or keys 51 so that if this key had been depressed, the operation of the first counting relay 1 would cause the cut-off relay 23 to open the circuit of the stepping magnet 24. It, therefore, follows that the number of impulses of current flowing through the winding of stepping relay 24 before the cut-off relay 23 shall open the circuit of the stepping relay, depends upon the particular controlling switch or key which had been depressed. The stepping relay is included in a loop which may be associated with the trunk line conductors 35 and 36 leading to the manual exchange shown in Figs. 2, 3 and 4, suitable switch contacts 37 and 38 being provided for making the connection when it is desired to signal a particular number of the manual exchange.

The signaling svstcm' includes also sequence switrhcs. the general functions of which are to establish in definite order at successive stages of the operation the inrious circuits required to bring into service the various apparatus in proper sequence. A form of sequence switch which I find convenient for this purpose comprises generally a movable switch operating member, a number of circuit changers actuated in sequence as said member is moved from one position to another, an electromagnet and motor m chanism operated or controlled by said magnet for advancing said movable member. In each position to which the movable member of a sequence switch is advanced a circuit or set of circuits is estab lished by which a given operation of the apparatus under control is made possible, and at the same time another circuit is established whereby the motor magnet of the sequence switch may be actuated to move automatically the sequence switch to its next position to establish a new set of circnits. -Sequcnce switches are, however, known to the art and therefore need not be further described herein. It should be un derstood, however, that my invention is not limited to use in connection with any particular form of sequence switch, but may be used in connection with any form which may be most suitable and convenient or with any apparatus performing equivalent functions.

In the circuit drawings the switch strings of the sequence switches are not shown in their actual arrangement, but are so located as to give the clearest arrangementof cirruits. The positions of the sequence switch in which any of its contacts are closed are indicated by numbers placed adjacent to such coiitacts: each contact being open in all positions. eg-icnot those indicated bv the adjacentnnmhers. In the case of the special contacts shown upon the drawings at 156 and 266 the numbers are placed on the opposite side of the contact anvil and indicate positions in which such contact is open, said contact being closed continuously while the rotary element of the sequence switch is in transit between the pos tions indicated.

'In the operation of the system the various digits designating the desired line are registered at the incoming end of the trunk line through the gency of a series of switching mechanisms which register the line designation by means of groups of lamps or other signal devices, the movement of the switchingr devices being: controlled by electrical effects set up by their own movement. such electrical effects operating and being deter-- mined through the sending! or controlling apparatus hereinhefore described.

The switching devices or registers referred to are shown in this disclosure of my invention as sequence switches. By reference to Fig. 4 of the drawings it will he seen that they each comprise the usual power and holding magnets. sequence switch contacts and the usual special sequence switch contacts. They each in addition. however. com prise a comn'iutating device adapted to make and break a circuit once for each position which the switch is adapted to take. Since sequence switches of this cl'iarrcter are known to the art. the structure of these registers will sufiiciently appear in the dci-icripiion of the operation thereof and no further description of the registers themselves is thought to he necessary. it should he noted, however, that my invention is not confined to use in connection with any particular form of reefistcr and such registers may he of any suitahle or convenient form and still come within the scope of my invention. In practice there will he as many of these registers employed as there are digits in the uumhcr of the line called, and th y will be su cessively operated to iudicatetho nuuiher desired in the manner hereinafter explained.

The cord in which the selected incoming trunk u-r ninatcs at the man ra! ex hange found and associatcd with the registers l y means of the c rd finding apraratus. This cord finding d vi e is illustrated in Fig. 1% of the circuit drawing and emlu'accs n t-oer ally a rotatahle hrush ca-ryinef shaft lltl carrying brushes l t} which are adaptrd to traverse stationary conta t n'ieinhcrs Hi5 arranged concentrically ahout said shaft. The shaft .40 carries at one cud an iron dish it?) which is adapted to he dz awn into 'l'rictional .driving relativ s with constantly driven I ower shaft 144;. by means of a powrr map:- not 145. A holding magnet H lo ated near the margin of the disk M55 is cacre'iy d when the circuit to the power magnet is inter rupted to attract said disk and stop the retation of the brush carrying shaft 140. Mounted upon said brush carrying shaft 140 is a contact making arm 14-7 the outer end of which in the rotation of said shaft 140 travels over a notched or toothed plate 148 mounted c mccnirically with said shaft 1 10. As it travels over said plate said arm closes. a contact through a spring 149. It will he noted that the spring 149 is 1 :0 located that the circuit therethrough will he completed only when a roller upon the outer end of the arm 14? is in one of the notches.

referring now in detail to the operation of the system, we will assume that the switches 37 and of the counting apparatus are hand-operated for convenience in explaining the operation, although in practice these switches will be operated automatically and mechanically in the ordinary course of a call. The battery 1752 is shown in several portions of the circuit diagrams on Figs. *2, 3 and t merely for clearness in illustrating the circuits and it will he understood that these several representations of hattery are to he considered as meaning a single battery, although if desired several batteries may he. employed. The same is true of the battery 26 in Fig. 1. As shown in the drawings. Fig. 2. the conductors and 36 of the trunk line terminate in springs 101 and 1 02 of the cord sequence switch 151'), which switch is initially controlled by call ing conditions in the trunk lines. Assuming now that the call has been started at the semi-niechanical xchange over the trunk line conductors 35 and 36 there will. be a circuit estahlished through the line relay 103 which circuit may he tinced from hattery 172. back contact and armature 10st of what is known as the second supervisory relay 10;), line relay 105). conductor 106, conductor 107. sequence switch contact 101, trunk conductor 3?, conl'a ct 3?, hack contact of cutoff relay Q3. stepping: relay 2%. contact. 38. trunk conductor sequence switch contact- 102 conductor 10$. armature 109 and its hack conta t of relay 105 to ground and haclr to battery. l pon the cncrgization of said line rctay its ariuatuw will he pulled up closing its front contact and thereby cs ahlishingr a circuit through the winding of the cord sequin-e ch 155. which. circuit may he traced from battery 172 through the power mac t of said. coral sentence switch;conductor 110. sequence switch contact lll, conductor lltl. front ontact and armature of the line elay 10? to ground and hack to halter This will cause th operation of said cord sequence switch 155 movingsam from its first 'o ccond position in which po i ion clo sequence switch contact 1'13 and, t ta ili llcs, a circuit through the pewcr magnet of the msition sequence switch 255. cat ins; sznne to move from its first into its second position. This switch,

circuit may be traced from battery 172 through the power magnet of the position sequence switch, contact 288, c nductor 189, sequence switch contact 113, front contact and armature of the line relay 103 to ground and back to battery.

In its second position the position sequence switch 265 completes a circuit through the winding of the power magnet 145 of the cord finder, from battery through the power magnet 145, back contact 190 of the test relay 194, sequence switch contact 292 to ground and back to battery. The energizaticn of the power magnet 145 causes the brushes 141 to rotate until they are brought into contact with contact members 142, one of which is grounded through se quence switch contact 114. \Vhe'n the orushes reach this position there will immediately he completed a circuit through the test relay 194, such circuit being traced from battery 172 through the relay 104, interrupter 147, the lower cord finder brush 141, the corresponding contact member 142, conductor 201 sequence switch contact 114 to ground and back to battery. The energization 01' the relay 1511 will open its back contact 190, thus interrupting the circuit through the power magnet 14;"; of the cord finder and will clcse its front contact 203 Which will con'iplete a circuit through sequence switch contact 202 and the winding of the holding n'nignet 140, energizing said magnet to hold the disk 143 against further rotation. Also the encrgization of relay 194 completes a circuit through the position sequence switch 265, which circuit may be traced from battery 172 through the power magnet of said position sequence switch, sequence switch contact 201, conductcr 205, front contact 5203 of the test relay 194, sequence switch conta t 202 to ground and back to battcry. This auses the position sequence switch to mot'c from its second into its third position in which position there is completed a circuit for the cord sequence switch 1.3.7, which causes it also to move from its second to its third position, the circuit in this case being traced from battery 172 through the power magnet of the cord sequence switch, conductor 110, sequence switch contact 115, conductor 907 and upper contact on the cord finder associated with the particular cord in use, the corresponding brush of the cord finder. sequence switch contact 200 to ground and back to battery. In its third positi n the cord sequence switch 155 opens the sequence and closes the sequence switch contact 116. This removes the connection which has heretofore existed between the front Contact of the line relay 103 and the position sequence and substitutes therefor a circuit from said front contact adapted to eoi perate w th the. respective registers as will he switch contact 1.1.3.

hereinafter described. In the third position of the cord sequence switch the sequence switch contacts 117, 118, 119 and 120 are also closed, whereby the cord circuit and the position sequence switch and the registers are associated for operation. At the same time the sequence switch contact 121 is closed to light the lamp 122, the lighting of which lamp indicates to the operator that a call is hein received and that it is associated with the particular cord circuit to which the lamp is individual. It will be also noted that immediately upon the position sequence switch leaving its first position, the sequence switch contact 288 has been opened, thereby isolating the position sequence switchfrom all of the cord circuits to which it is common other than the particular one which has started it in motion and with which it will now cooperate until its cycle of operations is ccmplete. The cord finding ()PQltlilOlI is now complete and both the cord sequence switch and the position sequence Siflitfl'l are in their third positions. in this position of the sequence switches the first of the registers, that is, the thousands indicatin register is now in coo erative re-Q lation to the cord circuit. A circuit now exists from the battery 172 through the motor, magnet 401 of the thousands register, conductor 40.), sequence switch contact 214, conductor 215, sequence switch contact 116, front contact and armature of the line relay 103 to ground and back to battery. The thousands register will thereupon begin to move. As the register moves it causes, by means of the impulscr 413, a ground to be placed on the conductor 217 each time it moves from one position tothe next, but as the register reaches each such position the ground is again removed. Each time the conductor 217 grounded, the stepping relay 21 of the sender or controlling apparatus will he deenergizcd, while the line relay 103 will he maintained energized. This is accomplished by reason of the fact that the grounding of the conductor 217 which conductor is connected by the sequence switch contact 117 and conductor 1.23 to the conductor 106, shunts the stepping relay 24 and at the same time provides an additional ground connection to maintain the circuit at the line relay 103. This causes the stepping relay 24 to permit its armature to retract which establishes an energizing circuit for the counting relay 1, the counting relay 11 having been energized and locked up when the circuit was first established through the stepping relay 24-, the switches 37, 38 and the line relay 103. I

If the switch 51 of the sender had been the one operated for thousands selection control, a circuit would now be established from the battery "20 through the cutoff relay 23, switch 51, front, Contact 61 of, the

counting relay 1 to ground and back to battery. This energizes the cut-otf relay 23 which by attracting its armature opens the contact 45 thereby opening the sending or controlling circuit and deenergizing the line relay 103 as soon the ground is again removed. from the conductor 217 by the further movement of the thousands register, which occurs when the register upon leaving its lirst or normal position has reached its second position; that is to say, the position in which the topmost of the series of contact devices associated with it is closed. lnnnediatrly upon the dei nergization of the iine relay 103 the energizing circuit for the power magnet L01 of the thousands register is opened at the front contact of the said line relay and the thousands register will thereupon stop and the lirst or top lamp of the thousands bank of lamps will be lighted. If, however, on the other hand, some other one oi the switches, 51, 53, it, etc., had been closed i'or thousands selection control the thousands register would continue to move intermittently shunting the stepping relay it until the counting relay associated with the switch which had been closed energized, when the cut oll relay will be energized and the thosuands register stopped in the corresponding position as has been hereinbefore described. That is to say, it the switch 54, for example, had been closed the thousands register would have to four times shunt the stepping relay 24 before 11h. action oi the cut-oti' relay :23 will stop the thousands register to light the fourth lamp of the thousands bank of lamps.

At the same timethat the line relay by the retraction of its armature opened the energizing circuit through the power magnet {01 of the thousands register at its l'ront contact. it closed a circuit at its back contact tor the position sequence switch 263. This circuit, which may be.traced l'iom the battery '17! through the power magnet of the position sequence switch, the sequence switch contact conductor 22(7 sequence switch contact llti back contact of the line relay 103 to ground and back to batteuv, causes the position sequence switch to move l rom its third into its seventh position. This movement of the position sequence switch opens the sequence switch contacts 292 and 209, the o1' ening of which is without effect at this time and also opens the sequence switch contact 2H. The opcnin; ol' the sequence switch contact 211- provents a subsequent closure olithe energizing circuit controlled by he ine relay to the thousands register and the closure of the sequence vswitch contact ill when the position sequence switch reaches its seventh position, shifts this energizing circuit to the hundreds register, It will be noted that the spec al sequence switch contact 266 oi;

the position sequence switch 265 is closed in the fourth, fifth and sixth positions of the sequence switch so that the position sequence switch upon leaving its third position continues to move until it reaches its seventh position, during which time the sequence switch contact is opened but is again closed as the switch reaches its seventh position. The register apparatus is now ready to respond to the necessary operations to designate the hundreds digit of the line desired.

Following the operation of the cut-off relay 23 terminating thousands selection, the switches 32 and 34 are operated and the depressed switch of the group 51, 58 inclusive is rel arsed. These operations may be performed manually or by any suitable means but in practice it is preferable and customary that these operations be performed automatically and mechanically and in the regular course of the establishment of the connection. The opening of the switches 32 and 34- restores all of the locked up counting relays to their normal positions. The same operation which has opened the switches 32 and 34 has also opened the switches 37 and 38. After the counting relays have been restored to their normal position one of the switches 51 to 58 is closed for hundreds selection control and the r-avitchcs :52, 34, 37 and 38 are again closed b ny desired means and the sender apparatus is now in condition to control hundreds selection. the sender or controlling circuit being closed throughout, energizing the stepping relay 24 and the line relay 103, the. cutoll' relay having been deinergized by the restoration of the counting relays. The operation of the hundreds register is substantially the same as that hereinbefore described of the thousands register and the details thereof need not be repeated. At the completion of the operation of the hundreds register the controlling circuit is again opened at the semi-mechanical exchange permitting the armature of the line rela 103 to again close the circuit at its bac contact and complete the circuit for the succeeding operation of the position sequence switch 265. In this operation said sequence switch is moved from its seventh to its eleventh position and the tens register is brought into cooperative relation With the sending or controlling apparatus.at the semiancc hanical exchange by the opening of the sequence, switch contact 241 and the closure of the sequence switch contact 231 The operation of said tens register is a substantial repetition of that of those already described, there being completed a circuit at the end of its operation which will cause the movement of pcsitiun sequence switch 265 from its eleventh to its fifteenth position in which the sequence switch contact 231 is opened and the sequence switch contact 232 is closed whereby the fourth or units register may be operated to designate the last digit of the called number. Upon the completion of the operation of the units regis ter the'armature of the line relay 103 will again drop back completing the circuit for the operation of the sequence switch 265 and moving same from its fifteenth to its sixteenth position. In this position of the position sequence switch 265 there is established a circuit through the cord sequence switch 15?, whereby said sequence switch is moved from its third into its ei hth position by reason of the fact that the special contact thereof is closed between the third and eighth positions of said switch. The circuit in this case may be traced from battery through the power magnet of said cord sequence switch, sequence switch contact 119, conductor 237, sequence switch contact 238 to ground'and back to battery. In this position of the parts the operator is now prepared to complete her call by inserting the plug 124 into the jack corresponding to the numbers indicated by the re istering devices as hereinbefore describe In completing this connection the operator first makes the usual busy test over the tip of the phw. conductor 125, back contact and armature 126 of rela the induction (301i 128, sequence switch c0ntact 129 to round. Upon finding that the line is not husy she inserts her plug fully into the jack. This operation completes a circuit from battery through a relay 127 to the sleeve spring of the line jack to ground through the usual cutoff relay. The energization of the relay 127 in this circuit estab lishes a circuit for the succeeding operation of sequence switch 155, which circuit may be traced from battery 172 through the power magnet of said sequence switch, conductor 110, sequence switch contact 120, conductor 130, front contact and armature 131 f the cord relay 127 to ground and back to battery. This circuit causes said sequence witch to move from its eighth position and this mmcmcut will be continued due to the special contact 156 until itcomes to rest in its eleventh position. In this movement, however, there is completed a circuit, through a restoring relay 5276, w hich in turn tl'irough sequence switch contact 269 completes a circuit through the position sequence switch 265, causing same to more from its sixteenth ito 'its seventeenth position. The circuit through said relay 271') may be traced from battery 172 through the winding of said relay, conductor 27 sequence switch contact 132, which closed in the ninth and tenth positions of cord sequence switch 15.), and by the special contact 156 of said cord sequence switch 155 to ground and back to 127, primary winding of' battery. The position sequence switch'265 in this seventeenth position closes contacts which complete circuits through the four registering devices causing them to move through the remainder of their cycle and to their normal position, the circuits being severally traced from battery 172, through the motor magnets 401, 402, 403, and 40% of the several registers, through the respective register contacts 405, 406, 407 and 408, conductors 417, 418, 419 and 420 and the sequence switch contacts 280, 281, 282 and 283 to ground and back to battery.

It will be noted that the register contacts 405, 406, 407 and 408 are all closed at all times except when the respective registers are in their normal positions and thereforethe movement of all of the registers to normal will immediately begin when the sequence switch contacts 280, 281, 282 and 283 are closed by the position sequence switch.

As soon as the registers have all reached their normal or first position in which position none of the indicating lamps are lighted the register contacts 405,406, 407 and 108 are opened and a circuit is completed from battery 172 through the power magnet of the position sequence switch 265, sequence switch contact 279, conductor 421, thousands register contact 422, hundreds register contact 423, tens register contact 424, units register contact 425, to ground and back to battery. The closure of this circuit causes the position sequence switch 265 to leave its seventeenth. position and come to rest in its first or normal position in which position the circuit just traced i again opened at the sequence switch contact 279. It should be noted that the energizing circuits, in response to the closure of which the respective registers more to normal. are all open at the contacts 405 to 108 in the first or normal position of such registors, and that each of them will therefore stop in its first or normal position. It should be further noted that. the particular order in which the registers reach normal position is immaterial, it only being necessary that each of them should have reached. its normal position in order to close the circuit. for the position sequence switch. The tour registers are now in their normal coudition and the position sequence switch with its associated apparatus is also in normal position. There being no normal position for the cord tinder itself no restoration thereof is necessary. The position sequence switch and the registers are now free to be associated with and cooperate with some other cord circuit other than the one over which we have assumed the call was received. and such operatimi with some other cord circuit will in no way affect or inter- 'l'ero with the ringing of the desired line.

the establishment of the talking circuit or the restoration of the apparatus associated with the particular cord to normal.

'Referring now particularly to Fig. 2 it w ill be recalled that the sequence switch has just passed from its eighth to its eleventh position. In the ninth, tenth and eleventh positions of this sequence switch, sequence switch contacts are closed to project ringing current out over the called line. The circuit of this ringing current may be traced from the grounded generator 133 through the ringing relay 131, sequence switch contact 135, one winding" of the usual induction coil which inductively connects the two portions of the transmission circuit, conductor 136, ring contact of the plug, out over the line and back again through the tip contact of the plug, conductor 137, sequence switch contact 138 and to ground. This will cause the signaling of the subscriber on the desired line, who removes his telephone receiver from the switch hook thereby permit ting in the usual way such an increase of current to pass that the rii'iging relay 131 will be energize thereby and attract its armature. Circuit will thereupon be closed from the battery 172 through the power magnet of the cord sequence switch 155, conductor 110, sequence switch contact 115, armature and front contact of the ringing relay 134 to ground and back to battery. The cord sequence switch will thereupon move from its eleventh position into its twelfth position which is the talking position and in which the sequence switch contacts 175, 176 and 177 are closed. The closure of the sequence switch contacts 175 and 176 has bridged across the inner terminals of the induction coils associated with the plug end of the connecting circuit a battery and a supervisory relay 178. This supervisory relay will be maintained energized so long as the called subscrihers receiver remains oil the receiver hook. A circuit will be established by the attracted armature of the supervisory relay 178 from the battery 172 through the second supervisory relay 105, cond ictor 179, sequence switch contact 177, front contact and armature ot' the supervisory relay 178 to ground and back to battery. The cnergisation of the second supervisory relay 105 has opened the original bridge across the trunk end of the cord circuit which included the line relay 103 and battery. and has substituted another bridge including the line relay alone. This bridge may be traced from the conductor 35 through the sequence switch contact 181,

conductor 107, conductor 106, line relay 103,

armature 101 and its front contact of the second supervisory relav 105. armatu e 109 and its front contact of: the 1 v- .v 105, conductor 108, sequence svvil. .n tJOIJwJlJ 182 and to conductor 36. The second supervisory relay has furthermore by its armature 109 and front contact bridged around the line relay a condenser 180. The line relay owing to the absence of battery will now be de't nergized.

At the same time that the bridge including the line relay 103 is changed by the second supervisory relay, the armature 18 1 of this relay is attracted to prevent the energization of the sluggish supervisory relay 185 which now through the sequence switch controls the operation of the lamp 122 which acts as a disconnectsignal. The circuit of this sluggish supervisory relay extends from the battery 172 through the sequence switch contact 186, slu gish supervisory relay 185, conductor 18%, to armature 181 of the second supervisory relay 105, and thence through either the front contacts of this armature and the armature of the line relay or through the back contacts of such a-rinatures to ground and back to battery. That is to say, to energize the sluggish supervisory relay 185 it is necessary that the second supervisory relay 105 and the line relay 103 be both energized or both denergized. The sluggish relay 185 is made sluggish for the purpose of avoiding detrimental ciiects if by chance the line relay should remain momentarily energized after the energization of the second supervisory relay 105 in response to the attraction of the armature of the first supervisory relay 178. Conversation may now continue between the calling line and; the called line as long as may be desired, the battery for the called subscriber being supplied from the battery 172 as indicated, it being notedthat the springs 101 and 102 were shiftedfrom the sequence switch contacts 195 and 196 to the sequence switch contacts 181 and 182 so as to include in the circuit the windings of the induction coil when the cord sequence switch moved from its third to its fourth position. \Vhen, however, conversation is over and the called subscriber restores his receiver to the receiver hook the circuit of the supervisory relay 178 is opened and such relay thereupon retracts its armature. This opens the circuit of the second supervisory relay 105 which in turn retracts its armatures and closes the circuit of the sluggish supervisory relay 185. This circuit being maintained the sluggish supervisory relay attracts its armature which closes a circuit for the cord sequence switch 155 which may be traced from the battery 172 through the power magnet of the cordisequence switch, sequence switch contact 197, arn'iature and -front contact of the sluggish supervisory relay 195 to ground and back to battery. The cord sequence switch thereupon moves from its twelfth into its thirteenth position and a circuit is thereupon established for the supervisory lamp 122 extending from the battery 172 through the supervisory lamp 122, sequence switch contact 198,

armature 18- and its rear contact of the.

second supervisory relay .105, back contact and armature of the line relay 103 to ground and back to battery. This illuminates the supervi ory lamp 122 which attracts the attention of the operator who thereupon knows that conversation has finished and that she may withdraw the plug from the jack of the called line. 'lhe operator thereupon withdraws the plug thereby destroying the energizing circuit of the cord relay 127. This cord relay thereupon allows its armature to retract and a circuit is thereby established for the cord sequence switch 155 which may be traced from the battery 172 through the power magnet of the cord sequence switch, contact 199, conductor 1-11, hacl: contact and armature 131 of the cord relay to ground and back to battery. The cord sequence switch thereupon moves from its thirteenth position and comes to rest in its first or normal position, passing through Without stopping the positions 11-, 15 and 16 in which positions the sequence switch contact 152 is maintained closed to prevent the opening of the trunk circuit, while the apparatus associated therewith at the manual exchange is being returned to normal. The entire apparatus is now again in its normal position and may be taken for use in connection with some other call as may be desired. I

In case the operator at the seini-mechani' cal exchange desires to interrupt the call before the same has been completed she can do so either in the second or the eighth po sition of sequence switch 155 by opening the c rcuit at the calling end of the line and permitting the armature ot' the line relay 11125 to drop back into its normal position. As will be seen in these two positions or. the sequence switch 155 there will he losed a sequence switch contact 137 which, if the armature of said line relay in its normal position will complete a cir uit through the locking relay 158, said relay being locked when once energized from the scro al to the twelfth position of sequence switch 13!) through the sequence switch conta t 1W3. The energization of the aforesaid relay will close through its armature 15S) and its front contact a circuit thiough the sequence switch 1.7.3, which circuit it will maintain closed continuously from the second to the twell'th positions of this sequence switch, causing it to more into its thirteenth position thereby lighting the 'lai'np 122 as a knockdown or disconnect signal for the operator at the manual exchange. Furthermorethe movement of the cord sequence switch due to the energization of the relay 158 will release the position sequence switch 965 which will thereupon be restored to t ormal and with it the registers precisely as occurred when the plug 121 was inserted in. the jack as above described. It should be noticed however, that when the relay 270 has once been energized whether as a result or the insertion of the plug 121 in the jack or some act of the distant operator it will he maintained energized over the locking circuit from battery 172, relay 270 and its locking armature sequence switch contact 272 to ground and back to battery Since the scquence switch contact 272 is closed in all positions of the position sequence switch from 2 to 16 inclusive this sequence switch is positively prevented from becoming stalled in one of the intermediate positions and as soon as the registers have again reached normal will itself be returned to normal position.

It will be understood that while I have shown certain specific circuits and apparatus embodying my invention, my invention is not limited to such circuits and apparatus, but includes in its scope any arrangement of circuits and apparatus performing similar functions and included within the terms of the hereinafter appended claims. It T'ill be further understood that the showing of the controlling or calling apparatus at the originating exchange or station is partial and diagrammatic and includes only such parts and apparatus as are necessary for an understanding of my invention and to typify the general h: ractc ot' the apparatus at the originat ng exchange or station with which the apparatus shown at the incoming exchange cooperates. It will he understood furthermore that this calling or controlling apparatus may be operated in any suitable man ner. e ther manually or, preferably, auto-- mutually, it being on y necessary that this aii paratus, in the operations thereof hereinbefore described. he so operated or controlled that the parts: are restored to normal and a new cont o ling circuit established through one of the swv tch s indicated and t xpili d at 51-1, 5;. etc., within the inter- .al while the postion sequence switch 2'33 is UK). lug from its third to it month position. again while this position sequence sw tch is moiing from its seventh to its elem-nth position, and again while it is inorin from. its clerenth to its fifteenth position. To accomplish this operation within the proper time any suitable or conven ent means may be used, or the operator may attend to these operations manually. but since the manner and means of" accomplishing these operations form no part. of my present inrcntion, they will not he described herein.

'nism for automatic exchange apparatus,

lines connecting said calling mechanisin' Having described one embodiment of my invention what I claim is:

1. The combination with a plurality of talking circuits, of an automatic calling device for setting up the number of a desired telephone station, a registering device, means for automatically as, ciating said de vice with any talking circuit taken for use and with said automatic calling device to disclose the number set up, and means for associating said register with anotl'ier talking circuit while said first talking circuit is still in use.

2. The combination with a plurality of independent circuits, of a, calling device connected With one of said circuits, a common registering device for registering the designation produced by said calling device, means to automatically connect said registering device with a circuit taken for use and to place said registering de ice under the control of said calling de ice, and means to free said registering device for common use while said line is still in use.

3. The combination with counting appa ratus for automatic exchange apparatus, of lines connecting said counting apparatus with a manual exchange, numerical indicating apparatus at said manual exchange adapted be associated with any one of said lines for indium ing a. call, said indicating apparatus embracing a plurality of registers, one for each digit of the number called, said registers being moved definite distances in response to said counting apparatus ,to determine corresponding digits of the number called, and indicating lamps brought into circuit in the operation of said registers to designate the number called.

st. The combination with calling mecha with a manual exchange, numericai indicating apparatus at said manual exchange em bracing a plurality of successively operated registers each moved a definite distance in response to said calling mechanism to determine one digit of the number called, contact devices carried by each of said registers, and a bank of lamps for each of said registers, the lamp in each bank designating the digit determined by its corresponding register being lighted through a circuit completed by one of said contact arms.

5. The combination with calling mechanism for automatic exchange apparatus, of lines connecting said calling echanism with a manual exchange, a coii at said manual exchange for each of said trunk lines terminating thereat, a numerical indicating apparatus at said manual exchange responsive to said calling mechanism, means for automatically associating said indicating ap paratus with any one of said cords, and sigcxchange for each na ling means for designating to the operator with which cord said indicating apparatus is associated.

6. The combination with calling mechanism for automatic exchange apparatus, of lines connecting said calling mechanism with a manual exchange, a cord at said manual of said trunk lines, a numerical indicating apparatus at said manual exchange responsive to said calling mechanism, switching means adapted to associate said indicating apparatus with a particular cord for purposes of receiving a call' and signaling means operated by said switching means to designate the cord with which said indicating apparatus is so associated.

7. The combination with calling'mechanism for automatic exchange apparatus, of lines connecting said calling mechanism with a manual exchange, a cord at said manual exchange for each of said lines, numerical indicating apparatus at said manual exchange responsive to said callingmechanism, switching means adapted to associate said indicating apparatus with a particular cord and means for finding the particular cord with. which said indicating apparatus is associated.

8, The combination with calling mechanism for automatic exchange apparatus, of lines connecting said calling mechanism Wit a manual exchange, a cord at said manual exchange for each of said lines, numerical indicating apparatus at said exchange responsive to said calling mechanism, switching means, adapted to associate said indicating apparatus with a particular cord, and means operated by said switching means for find ing the particular'cord.

i). The combination of semi-mechanical exchanges and a manual exchange, of trunk lines connecting said semimechanical exchanges with said manual exchange, a cord at said manual exchange for each of said trunk lines, a numerical indicating apparatus, switching means adapted to associate said indicating apparatus with a particular cord, means operated by said switching means for finding the particular cord, ad

a signal operated upon the completionof the cord finding apparatus to designate the particular cord in use.

10. The combination of a semi-mechanical exchange and a manual exchange, of trunk lines connecting the same, a numerical indicating apparatus at said manual exchange, means for automatically connecting said indicating ap aratus with any one.of said trunk lines or purposes of indicating a call, and means for automatically disconnecting it therefrom as soon as such call is com p eted.

i. The combination of asemi-mechanical exchange and a manual exchange, of trunk indicating apparatus from a particular cord,

said means lasing controlled by the insertion of the plug oi that cord into a jack.

12. The combinat on of a semi-inechanical exchange and a manual exchange, of trunk lines connecting the same, a cord at said manual exchange for each of said trunk lines, each of said cords being provided with a .plug, a sequence switch associated with each cord, a numerical indicating apparatus, a second sequence switch adapted to associate said indicating apparatus with any one of said cords, and means, controlled by the insertion of the plug of that cord into a ack, operating said sequence switches to reset the recording apparatus preparatory to receiving a succeeding call.

In Witness whereof, I hereunto subscribe my name this 17th dav of Sept. A. I). 1910.

FRANK R. Mi BERTY.

Witnesses F. T. WOODWARD, IRVING MACDONALD. 

